The present invention relates, generally, to a transmitter and receiver combination for measuring a parameter, pressure, force, or weight, within a vessel, and more particularly, to a sensor unit including a transducer and an infrared generator cooperating therewith, for transmitting infrared signals to a remote receiver unit including a measurement display.
Measurements of physical parameters related to various vessels, containers or equipment need to be taken in order to ensure maximum safety, and efficiency. Unfortunately, taking the measurements is often difficult, time consuming, or dangerous. Taking the measurements is often difficult because the gauges or displays for providing the needed measurements are often located in places which are difficult to view. For instance, truck tire gauges are notoriously difficult, unpleasant, and time consuming to view as discussed in Ser. No. 07/453,785.
Taking measurements is often time consuming because gauges or other devices for displaying the physical parameter must be viewed by a human being. An inspector often must record such measurements for a large number of vessels. Unfortunately, the gauges are often difficult to read and often require physical contact in order to make measurements. For example, a fire inspector or other building personnel may be required to determine if all the fire extinguisher devices in a particular building are adequately filled or fully charged by reading a small gauge which is often obscured by other equipment. Even more difficult, some types of fire extinguisher devices can only be measured by physically weighing the device. Thus, reading gauges manually is time consuming and expensive.
Also, taking measurements is time consuming because data must be recorded by hand. Besides recording the measurement, the inspector is usually required to write down all relevant information pertaining to the inspection of the multitude of fire extinguisher devices. For instance, the inspector is expected to record data such as date, time, and unit identification along with the measurements. This procedure is time consuming and leaves many opportunities for inspector error.
Taking measurements can be dangerous to both humans and the environment. Frequently, the measurement process involves exposure to harmful matter or dangerous moving parts. For instance, refrigerators, air conditioners, and other cooling devices contain ammonia or other dangerous chemicals. Frequently, measuring the quantity of ammonia or freon in a device requires opening the system and attaching a pressure gauge. Inevitably ammonia or freon is released into the environment. Even worse, large amounts of ammonia or freon are often accidentally spilled when taking measurements.
Thus, a low cost system for measuring physical parameters of various types of vessels, containers or equipment is needed which improves ease, efficiency, and safety.
The present invention provides a remote sensing and receiving system including a sensor unit and a remote receiver unit. The sensor unit includes a transducer disposed to sense the physical parameter of an apparatus. The transducer generates an electric signal representative of the magnitude of the physical parameter and applies this signal to an LED driver. The LED driver modulates an LED, which transmits an infrared (IR) signal.
The remote receiver unit receives a modulated IR signal and applies the IR signal to a processor. In response, the processor drives a digital display, which produces visual indicia indicative of the magnitude of the physical parameter.
The present invention also can be configured to allow for two-way communication between the sensor unit and remote receiver unit. The receiver unit controls the sensor unit by transmitting activation signals for turning the sensor unit on, reading signals for requesting data from the sensor unit, and writing signals for transmitting data to the sensor unit. The sensor and the receiver unit each have a transmitter and a receiver to enable communication through pulses of carrier signals. The data communicated can be stored in memory in the sensor unit or the receiver unit.